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Answers

1. According to the order of operations, things in parentheses get calculated first. That’s how you get this: 6 ÷ 2×3 = 9.

2. #3.

3. The boys have 12 chocolates together.

4. According to Archimedes’ Principle, the weight of the submerged piece of ice is equal to the weight of the fluid that is displaced by the ice. At first, the water level was lowered. But when the ice melted, it turned into water of the same weight. That’s why the water level won’t change.

5. To solve this puzzle you need to "turn back" time. First, 1 hour and 10 minutes back, then 1 hour and 20 minutes, and finally 1 hour and 30 minutes. Therefore, if you do the same to clock #4, you’ll get the time that clock #5 shows: 5:35.

7. Any object submerged in water has an apparent weight loss equal to the weight of the fluid displaced. The stone takes up more space than the iron balance weight. Therefore, the stone will displace more water and thus will become lighter. That will tilt the balance.